DE1902435A1 - Device for low-pressure manifold injection for motor vehicles - Google Patents

Description

D e c e r i n g e Device for low-pressure intake manifold injection for motor vehicles The invention relates to a Sinrichtung tur low-pressure intake manifold injection of fuel for motor vehicles.

With this type of mixture preparation, the fuel is by means of a number of spray nozzles corresponding to the number of cylinders with pressures in the range injected into the intake manifold from 1 - 3 atmospheres in front of the engine's intake valves. With modern Devices are electronically controlled, electromagnetically switched valves used, to which the fuel is supplied at constant pressure, with the fuel metering then takes place through variable dimensioning of the valve opening times.

It was previously of the opinion that it would lead to optimal results with regard to Fuel consumption and emission control result when injecting the fuel takes place in the suction stroke. Accordingly, you have the start of opening for all injectors provided differently, d. i.e., during a duty cycle (720 ° CA) in the case of a four-cylinder engine, four opening impulses shifted in time against each other needed.

However, two injection valves each have already been operated synchronously. eg happened only to make the electronic control cheaper and below alleged abandonment of the technically optimal solution.

The invention is based on the consideration and its metrological verification, that the exhaust gas composition by the choice of the injection time within a Duty cycle (7200 KW) is hardly influenced and that also the specific fuel consumption does not depend significantly on it.

The invention therefore proposes an injection device with injection valves changeable opening times to control the start of opening of all valves synchronously. The solution to the injection can be achieved by a cam in conjunction with a electrical contact set.

The invention is explained below using an exemplary embodiment will.

In the attached figure is an electronically controlled one schematically Injection device according to the invention shown.

The fuel is drawn from the tank 1 via a filter 2 by an eccentric pump 3 sucked in and with constant pressure in the supply lines 4 to dOn injection valves 5 pumped. To keep the pressure in front of the injection valves 5 constant a pressure relief valve 6 and a return line 7 ¢ the electronic one serve at approx. 2 atm Control unit 8 for determining the variable opening time of the valves is only indicated schematically. It receives its control impulses from various measuring instruments and circuit elements such as intake manifold pressure sensors, temperature sensors and throttle valve switches, however, their circuitry details for the present invention are not are essential. The control unit @ is triggered by the ignition distributor 9, whereby according to the invention it does not affect the phase position of this triggering pulse arrives and it is not necessary forner, this Ispuls in the Sten @@ gerä @ accordingly the view @ d @ r injectors to duplicate. The electronic @@@@@ ektung is thus considerably simplified by the fact that it @@@ ord of a work cycle @ @ needs to give an opening impulse once to all injection valves at the same time.

Claims (1)

() P a t e n t a n s p r u c h Device for low-pressure intake manifold injection of fuel for motor vehicles with electromagnetic injection valves assigned to each cylinder, their changeable opening times and opening phases by electronic means are controllable, characterized in that in NehrzJlindermotoren all injection valves be controlled in the same way. L e r s e i t e